SimCenter Forum

Research in Natural Hazards Engineering => Wind Engineering (WE-UQ) => Topic started by: azing on June 28, 2021, 09:45:03 PM

Title: Load factor
Post by: azing on June 28, 2021, 09:45:03 PM

Hi,

When performing WE-UQ simulation of a 20-story frame with one sample and a dummy variable, I realized that the results don't match with pure OpenSees simulation results. This is because I was using a load factor to scale up the magnitude of the applied wind forces. I realized that if I specify the load factor as 1, but use a wind loading s enario that has been externally scaled before being used in WE-UQ as an input, then the results will match with OpenSees. It seems to me that the load factor input in the "existing" of the tool doesn't apply the factor properly. Is this a possibility or am I making a mistake somewhere else?

Thank you,
Azin

Title: Re: Load factor
Post by: fmk on June 29, 2021, 05:05:43 AM

Azin

I will need your files to see what is up.

frank

Title: Re: Load factor
Post by: azing on June 30, 2021, 09:17:08 AM

Thank you so much, I really appreciate it. I have uploaded the files to the message.

I am running these simulations for different wind speeds starting from 36mph. I am using the "existing" wind event option to be able to use different wind directions as loading scenarios. since I have 20 loading scenarios which take time to set up, I just created the loading files for 36mph and then changed the loading time step and added a load factor to scale up the forces.

The attached folder shows the simulation files for 56mph.

The "unfactoredLoad" folder contains the model with 36mph loading file which is scaled up using a scale factor of 2.4198. This doesn't give me reasonable results.

The "factoredLoad" folder contains the model with a loading file that I created for 56mph so it doesn't need to be scaled up. So I use a load factor equal to 1 for this one. This gives me reasonable results that match with pure OpenSees simulation results.

* couldn't upload the event files due to large size. 

I am just don't know what I am doing wrong in using the load factor. 

Title: Re: Load factor
Post by: fmk on July 07, 2021, 04:24:50 PM

the event files were not in what you sent .. in addition to scaling the load factor do you also scale the timestep?

https://nheri-simcenter.github.io/WE-UQ-Documentation/common/technical_manual/desktop/WEUQ/scalingWindTunnelData.html

Title: Re: Load factor
Post by: azing on July 08, 2021, 06:32:44 PM

yes, I have scaled the time step as well.

The event files are large in size. When If I attached them to the message, the message could not be delivered. Can I email them for you?

Title: Re: Load factor
Post by: fmk on July 12, 2021, 10:00:26 PM

sorry send via email: fmckenna AT berkeley DOT edu

Title: Re: Load factor
Post by: azing on July 13, 2021, 10:59:10 PM

Thank you so much, I sent it to you.